The technology of the present disclosure relates to an optical scanning device and an image forming apparatus.
In general, an optical scanning device mounted in an image forming apparatus such as a copy machine has a light source, an optical deflector that deflects optical beams emitted from the light source and allows the deflected optical beams to be scanned in a main scanning direction, and an image forming lens that forms an image of the optical beams, which have been deflected and scanned by the optical deflector, on a surface to be scanned at a constant velocity.
In this type of optical scanning device, the temperature of the image forming lens is changed according to the operation of the optical deflector, resulting in a change in a bending modulus thereof. Therefore, there is a problem that the position in the main scanning direction of scanning light having passed through the image forming lens changes and thus image failure (image failure such as a color shift in the case of a color machine) occurs.
In this regard, there is proposed a technology of detecting the surface temperature of the image forming lens by a temperature sensor and correcting a writing position or a writing start timing of an image on the basis of the detected temperature, thereby correcting a position shift in the main scanning direction of the scanning light. The temperature sensor is provided at an upper side of the image forming lens.